Going too far: Yes, most OWI laws, including Iowa's, allow you to charge someone under the legal limit, or without a breath test, because they include language prohibiting driving "under the influence" without mention of a blood alcohol level. That obviates the problem of test refusals (a Fifth Amendment right) or intoxication by some other substance. But this Washington DC situation demonstrates the problems with this:

Debra Bolton had a glass of red wine with dinner. That's what she told the police officer who pulled her over. That's what the Intoxilyzer 5000 breath test indicated -- .03, comfortably below the legal limit. She had been pulled over in Georgetown about 12:30 a.m. for driving without headlights. She apologized and explained that the parking attendant must have turned off her vehicle's automatic-light feature.

Bolton thought she might get a ticket. Instead, she was handcuffed, searched, arrested, put in a jail cell until 4:30 a.m. and charged with driving under the influence of alcohol.

Bolton, 45, an energy lawyer and single mother of two who lives in Alexandria, had just run into a little-known piece of D.C. law: In the District, a driver can be arrested with as little as .01 blood-alcohol content.

As D.C. police officer Dennis Fair, who arrested Bolton on May 15, put it in an interview recently: "If you get behind the wheel of a car with any measurable amount of alcohol, you will be dealt with in D.C. We have zero tolerance. . . . Anything above .01, we can arrest."

At some point, there's going to be a backlash, guys. This and the Harry Potter thing via Concurring Opinions.